Lists in Firefox: Unable to add text after text navigating to start of list item

[nelson-yu]

Bug Description

This occurs in Firefox Only. When using the CTRL/CMD + Left Arrow Key to navigate the cursor to the start of the list item, text cannot be added.

Screen.Recording.2026-06-11.at.1.08.10.PM.mov

Steps to Reproduce

1. Open Quill in Firefox
2. Add a list item
3. Press CTRL/CMD + Left Arrow Key to navigate the text cursor to the start of the line
4. Attempt to add new content

Environment

Quill: 2.0.3
Browser: Firefox 151.0.4

[matt-the-thew]

I can reproduce this consistently on Firefox 151.0.4 / macOS (M2).

Confirmed it does not occur on Safari 26.5 or Chrome 149.0.7827.200, so this looks Firefox-specific, possibly a difference in how Firefox handles cursor positioning or selection collapse after Ctrl/Cmd+ArrowLeft versus the other engines.

Notable behavior that once Ctrl/Cmd+ArrowLeft is entered, jumping forwards by words with Ctrl/Cmd+ArrowRight is not possible, and cursor requires two arrowRight inputs to navigate one character forward. Following this, behavior is nominal.

I'd like to take this one, WIP, will follow up shortly.

[matt-the-thew]

Failed to realize this project was not actively maintained.
Happy to complete this work upon being assigned to this issue by a maintainer.
Cheers.